Bag tube feeding and closing means

ABSTRACT

A feed table is disclosed for feeding successive bag tube ends past a sewing head for closing the tube ends; a work conveyor belt system feeds the bag tubes past the sewing head and a plurality of infeed chains with upwardly extending lugs feed successive bag tubes onto the work conveyor belt feed system with positive infinitely variable transmissions providing independent adjustment of the work belts and the infeed chains and microswitch means engageable with completed bags downstream of the sewing head for actuating a pneumatic knife to sever the tape section between adjacent bags with the infinitely adjustable transmission driving the infeed chains enabling conversion from one bag size to another while maintaining proper spacing between bags passing through the sewing head.

[ Jan. 1,1974

lJnite States Patent 91 Robinette BAG TUBE FEEDING AND CLOSING Primary Examiner-Alfred R. Guest MEANS Attorney-Thomas B. Van Poole et a1.

[75] Inventor: James A. Robinette, Bristol, Tenn.

[57] ABSTRACT A feed table is disclosed for feeding successive bag [73] Assignee: Strong-Robinette Bag Company,

11nc., Bristol, Tenn.

Nov. 21, 1972 Appl. No.: 308,445

22 tube ends past a sewing head for closing the tube ends; 1 l e a work conveyor belt system feeds the bag tubes past the sewing head and a plurality of infeed chains with upwardly extending lugs feed successive bag tubes onto the work conveyor belt feed system with positive infinitely variable transmissions providing independent adjustment of the work belts and the infeed chains and [52] US. Cl. [51] Int. [58] Field of microswitch means engageable with completed bags downstream of the sewing head for actuating a pneu- [56] References Cited UNITED STATES PATENTS matic knife to sever the tape section between adjacent bags with the infinitely adjustable transmission driving 112/10 the infeed chains enabling conversion from one bag 112/10 size to another while maintaining proper spacing between bags passing through the sewing head.

1,731,295 10/1929 Cornell................................. 2,260,191 10/1941 Orr..........

2,700,947 2/1955 Wilson Dickmann............................. 112/10 15 Claims, 9 Drawing Figures PATENTEDJAN 1 I974 SHEEI 2 BF 7 NON PATENTED JAN 1 I974 SHEET 3 OF 7 PATENTEDJAN 1 m4 SHEET 5 OF 7 PATENTEDJAN 1 3.782.305

sum NF 1 NmN wom

, l BAG TUBE FEEDING AND CLOSING MEANS This invention is in the field of bag fabricating apparatus and is specifically directed to the field of sewing apparatus for closing one end of a paper bag tube by stitching a tape over the tube being closed.

Prior known devices for closing the ends of bag tubes have employed sewing tables in which a pair of infeed chains having attached feed lugs extend upwardly above the table surface for feeding the bags to conveyor belts for conveying the bags past the sewing head. Apparatus of the foregoing type requires removal of the feed chains and repositioning of the lugs on the chains when changing from one bag size to another.

This changeover has been quite time consuming and necessitates the closing down of the machine during the change-over to the consequent economic loss of the operator.

Therefore, it is the object of the'present invention to provide a new and improved means for sewing bottoms onto paper bags and the like.

Yet another object of the invention is the provision of new and improved means for sewing bottoms on bag tubes which is easily convertible from one size bag to another bag size.

Obtainment of the objects of this invention is enabled through the provision of a feed table having two conveyor systems. The first conveyor system consists of an infeed conveyor in the form of a plurality of driven chain members having feed lugs extending outwardly through slots in the feed table with the lugs being mounted on the chains in parallel array so that the lugs engage the side edge of each bag and feed the bag forwardly across the table surface. The bags are fed onto a work conveyor comprising a plurality of feed belts arranged in parallel array with their upper flights extending along the work table surface for conveying one end of the bags past a sewing head. A tape is folded over the bag end at the sewing head and is sewn in position by the conventional sewing means. As soon as the bag clears the sewing head, it engages three successive microswitch elements which serve to actuate a solenoid valve for actuating a pneumatic knife for severing the tape segment between adjacent completed bag members.

The work feed conveyor belts are driven at a slower speed than are the feed chains and power to the work feed belts and the chains is applied from a single motor source through individual positive infinitely variable transmission members which enable an accurate adjustment of the conveyor speed. It is possible to adjust the speed of the chain members in a matter of seconds by the simple manual twisting of a knob when changing from one bag size to another in order to insure accurate optimum positioning of adjacent bag members fed onto the work feed belts.

A better understanding of the manner in which the preferred embodiment of the invention achieves the objects of the invention will be enabled when the following written description is read in conjunction with the appended drawings in which:

FlG. l is a perspective view of the preferred embodiment;

FIG. 2 is a top plan view of the preferred embodiment; FIG. 3 is a rear elevational view of the preferred embodiment;

FIG. 4 is a sectional view taken along lines 4-4 of FIG. 3;

FIG. 5 is a sectional view taken along lines 5-5 of FIG. 3;

FIG. 6 is a sectional view taken along line 6'-6 of FIG. 5;

FIG. 7 is a diagrammatic perspective view of components of the preferred embodiment illustrating the mode of operation thereof;

FIG. 8 is an enlarged perspective view of a bag and the method of closure thereof; and

FIG. 9 is a schematic pictorial circuit diagram illustrating the control means employed in connection with the cutting means for seving the tape extending between adjacent completed bag members.

Attention is initially invited to FIGS. 1 and 2 of the drawings which illustrate the preferred embodiment of the invention which includes a main frame member having vertical corner posts 20, lower horizontal end frame members 22 and lower horizontal side frame members 24. The upper ends of the vertical corner posts 20 support upper horizontal end frame members 26 and upper horizontal side frame members 28 which provide support for a feed table 30 and a conventional bag closing means including a sewing head 32.

A work conveyor for conveying tubular bag blanks or tubes past the sewing head 32 is provided in the feed table 30 and comprises four driven work feed belts 34 having their upper flights extending above the upper surface of the table 30 as shown in FIGS. 1 and 2.

An infeed conveyor is also provided on table 30 with the infeed conveyor including four driven chains 36 with each of the chains 36 having upwardly extending pivotal feed lugs 38 extending above the upper surface of the table 30 and controlled by a cam 41 as shown in FIG. 6. It should be noted that the chains 36 are mounted on upstream sprockets 37 and downstream sprockets 35 which are respectively supported by shaft members 31 and 33 as shown in FIG. 6. Movement of the chains and their associated feed lugs 38 serves to feed individual bag blanks to the work conveyor belts 34 for closure of the bag blank ends by operation of the sewing head 32. The infeed conveyor system also includes three continuously rotating positioning rollers 40 rotating in the direction of the arrows associated with the rollers in FIG. 2 for moving individual bag tube blanks into proper lateral position with respect to the sewing head by engagement with a side guide plate 42 prior to movement of the bag to and through the sewing head 32.

It should be initially noted that bag blanks are placed on the table and conveyed by the feed lugs 38 to the work feed belts 34 which then convey the bag blanks through the sewing head 32 to close one end of the blank. A bag hold-down belt 44 supported on rollers 46 and 48 respectively mounted on shafts 50 and 52 extends alongside and adjacent the sewing head 32 for holding the ends of the bags being sewn. The lower flight of the hold-down belt 44 is engaged on its upper surface by a plurality of floating rollers 53 of conventional construction.

The basic steps in the operation of the inventive device are illustrated in FIG. 7 and include the positioning of a bag tube on the infeed portion of the table as exemplified by bag Bl followed by movement of the bag tube Bl. in the direction of the arrow on the bag over into engagement with the side guide plate 42 by virtue of the continuous rotation of the rollers 40. The bag tubes must obviously be formed of sufficiently stiff material, such as paper or the like, to enable the positioning by rollers against guide plate 42 without crumpling of the tubes. The bag is engaged by lugs 38 and moves to the right in the manner of bag tube B2 so that the bag is fed onto the work conveyor belts 34. The end of the bag tube moves under the hold-down belt 44 as illustrated by bag B3 and a paper tape 54 being drawn from a supply roll 55 is folded over the end of the bag by a conventional tape guide 57 as the bag moves into the position illustrated by bag B4 in FIG. 7. A paper filler cord 56 is applied to the upper surface of the tape 54 so that operation of the sewing head 32 stitches the tape and filler cord to and across the end of the bag as shown in FIG. 7. The sewing operation is being performed on bag B5 in FIG. 7 with the details of the sewing operation being illustrated in FIG. 8.

As the sewing operation on one bag, such as bag B6 in FIG. 8, is completed, the sewing head 32 continues to operate with a connecting portion 58 of the tape extending between the completed downstream bag B6 and the next upstream bag B7 which is in the process of being sewn by the sewing head 32. A pneumatically actuated knife blade 60 is actuated to sever the connecting portion of tape 58 along a cut line 62 as illustrated in FIG. 8 with the cut line 62 being positioned medially between the adjacent bags B6 and B7. Following the cutting operation of blade 60, the bags move to the right as illustrated by bag B8 and are discharged from the conveyor belt 34 as illustrated by bag B9. It will be appreciated that the connecting portion of tape 58 should be of relatively small size in order to avoid waste of the tape and to keep tags 64 on each end of the completed bag from being overly long. In addition, the timing ofthe operation of the knife blade 60 is obviously of critical importance. Changeover from bags of one width to bags of another width has been a time consuming procedure with prior known bag closure devices; however, the present invention eliminates the problems with the prior known devices in a manner which will become apparent from a study of the following description of the drive and adjusting means for controlling the operation of the bag conveyor components and the knife 60.

Attention is now invited to FIGS. 1, 3 and 4 which illustrate the primary drive and adjustment components of the subject invention. An electric motor 66 controlled by push-button assembly is mounted on adjustable support means 68 and constitutes the sole power source for the entire apparatus. Power from motor 66 is supplied to a centrifugal clutch 70 from which a belt 72 extends to a spring loaded variable pitch V-belt pulley 74 on the input shaft of a speed reducer 76. The speed of rotation of pulley 74 can be varied somewhat by adjusting the position of motor 66 by the adjustable support means 68.

An output pulley 78 coaxial with the V-belt pulley 74 provides a relatively high speed power output to a splined belt 80 extending upwardly to an upper input pulley 82 mounted on the end ofa drive shaft 84 (FIG. 4) supported for rotation on the frame means. An output pulley 86 is keyed to the opposite end of drive shaft 84 with a second splined belt 88 extending about the output pulley 86 and upwardly over a power input pulley 90 on the conventional sewing head 32.

Power for driving the work conveyor belts 34, the infeed chains 36 and the positioning rollers 40 is supplied from the low speed power output sprocket of the speed reducer 76 to a main drive chain 102 which also extends over an input sprocket 104 of a primary positive infinitely variable speed transmission 106 of conventional design which has an output sprocket 108 and a speed adjustment sprocket 110. Speed adjustment sprocket 110 is connected by a chain 112 to a manual adjustment knob 114 on a shaft 115 which, when rotated, serves to adjust the ratio of the input speed to sprocket 104 and the output speed of sprocket 108. A similar knob 114' is located on the other end of shaft 115.

Power from the output sprocket 108 of transmission 106 is conveyed by a chain 116 to a reversing transmission 118 having coaxial output sprockets 120 and 122 (FIG. 1). A chain 124 extends from the output sprocket 122 to an input sprocket 126 ofa second positive infinitely variable speed transmission 128 and a chain 180 extending upwardly from sprocket 120 for a purpose to be discussed hereinafter.

Variable speed transmission 128 includes a power output sprocket 130 from which a chain 132 extends upwardly to a sprocket 138 keyed to the end of shaft 33 which serves as a supporting drive shafts for chains 36. In addition, shaft 33 is provided with a plurality of bevel gears 218 for driving rollers 40 as shown in FIG. 2.

The second variable speed transmission 128 also includes a speed ratio adjustment sprocket 140 from which a chain 142 extends upwardly about a sprocket 144 keyed to a shaft 146, as shown in FIG. 5. An adjustment knob 148 on one end of shaft 146 is manually rotated to effect an adjustment in the ratio of the input speed to the sprocket 126 to the output speed from the sprocket 130. A second adjustment knob 148 is keyed to the shaft 146 on the other end from knob 148 and a chain extends from a sprocket 162 on shaft 146 to an intermediate sprocket 164 on a stub shaft 166. A second intermediate sprocket on stub shaft 166 supports a chain 168 connected to a sprocket 169 on a bearing supported rotary indicator shaft 170. A pointer 172 is mounted on the other end of the rotary indicator shaft adjacent a dial 174. Dial 174 includes indicia abouts its periphery which, in conjunction with pointer 172, is indicative of the width of the bag for which the machine is adjusted to feed at any particular time.

It should be noted that adjustment of either of the adjustment knobs 148 or 148' serves to adjust the output speed from the second variable speed transmission 128 and consequently serves to adjust the speed of the chains 36 feeding the bag blanks onto the work conveyor belts 34. The importance of this adjustment will become apparent hereinafter.

Output power from the sprocket 120 on the reversing transmission 118 is conveyed by a chain (FIG. 1) to a sprocket 182 on the end of a shaft 184. Shaft 184 has a pinion 186 adjacent its other end meshing with a second pinion 188 keyed to the end of a longitudinal drive shaft 190 illustrated in FIG. 3. The opposite end of drive shaft 190 is provided with a second pinion 192 meshing with a pinon 193 keyed to a transverse shaft 194 (FIG. 4) extending across the width ofthe table 30.

An output drive sprocket 196 is provided on the outer end of shaft 194 and a chain 198 extends upwardly from sprocket 196 over a sprocket 200 keyed to the end of conveyor drive shaft 202. Conveyor drive shaft 202 supports drive rollers 204 over which the work conveyor belts 34 extend. The other end of the conveyor belts 34 is supported by idler rollers 138 on a shaft 136.

Pinion gear 206 is keyed to the conveyor shaft 202 adjacent the sprocket 200 and meshes with a pinion gear 208 keyed to the end of shaft 50 which has the hold-down belt supporting drive rollers 46 keyed to its other end.

Knife member 60 is mounted for pivotal movement about pivot 230 upon actuation of an air cylinder 232 as shown in FIG. 9. A normally closed microswitch 234 is positioned to be engaged by the blade 60 upon actuation of the blade for movement through a cutting stroke. Compressed air is supplied to cylinder 232 through hose members 236 and 238 from a valve 240 operated by a valve solenoid 242. A holding relay 244 is connected to one terminal of solenoid 242 by conductor 300 which is connected to a power line L1 as shown in FIG. 9. In addition, the holding relay is also connected by line 302 to one contact of the normally closed microswitch 234 with a line 304 connecting the other contact of switch 234 to a movable contact 245 of holding relay 244. A conductor 306 extends between movable contact 245 and the other terminal of valve solenoid 242.

The speed of operation of the infeed conveyor chains 36, the work feed belts 34 and the sewing head 32 are all adjustable simultaneously in the same direction by operation of the adjusting means 68. Moreover, the speed of the chains 36 can be adjusted with respect to the work feed belts 34 by operation of the adjustment knobs I48 or I48 controlling the variable speed transmission 128. However, the speed of chains 36 always exceeds the speed of belts 34 in order to insure that the bags are accurately positioned on belts 34 by movement of lugs 38 and chains 36. In addition, the speed of chains 36 and belts 34 can be adjusted simultaneously in the same manner by adjusting the variable speed transmission 106 by means of the knobs 114 or 114'. Adjustment of the aforementioned type would adjust the conveyor speed of the belts 34 with respect to the sewing head.

Three microswitches are supported immediately downstream of the sewing head 32 on a horizontal frame element 260 as shown in FIGS. 3 and 9 with microswitch members comprising an enabling switch 250 having a pivotal actuator arm 251 normally biassing the switching into an open condition, a cut initiate microswitch 252 having a pivotal actuator arm 253 normally holding the switch in a closed condition and a third microswitch 254 having a pivotal actuator arm 255 normally holding the switch in an open condition.

Power from source L2 is supplied by a line 305 to one terminal of switches 250 and 254 with the other terminal of switch 250 being connected to a conductor 307 which in turn is connected to the other terminal of switch 254. Switch 252 has one terminal connected to conductor 307 with its other terminal being connected to a line 306 connected to a conductor 302.

It should be noted that the switches 250, 252 and 254 are adjustably mounted on support 260 adjacent each other immediately downstream of the sewing head 32 so that a bag B moving from the sewing head will engage the pivotal actuator levers 251, 253 and 255 in sequence as the bag is conveyed by the belts 34 etc. The

position of adjustment of the switch members on the support 260 determines the position of out line 62 between adjacent bags.

The manner of operation of the preferred embodiment will now be described with it being initially assumed that the apparatus is in operation with the speed of the chains 36 and the belts 34 being properly adjusted. The operator of the machine stands in the position illustrated in FIG. 2 and sequentially places individual bag blanks on the table 30 immediately in front of his position so that the individual bag blanks are engaged by the continuously rotating driven positioning rollers 40 to be moved over against the guide plate 42. In addition, the upstream edge of each bag blank is engaged by a set of the parallel lugs 38 positioned in a line perpendicular to the direction of movement of the chains 36. The first bag is moved forwardly onto the work belts 34 and under the hold-down belt 44 through the sewing means 32 where the tape 54 is folded over the bottom end of the bag and is stitched in place along with the paper filler cord 56 by the operation of the sewing head. As the first bag moves from the sewing head, its forward edge engages the lever 251 of the enabling switch 250 to cause the contacts of the enabling switch to close. Since the contacts of switch 252 are closed at the time the contacts of switch 250 are closed by the forward edge of the first bag, line current from line L2 through switch 250, conductor 307, switch 252, conductor 306, conductor 302, the coil of holding relay 244 and line 300 to line L1 so that the holding relay is actuated and the movable contact 245 moves into engagement with the fixed contact 246. Valve relay 242 is simultaneously actuated with holding relay 244. Closing of the contacts 245, 246 of holding relay 244 connects line voltage line L2 to one terminal of the closed microswitch 234 so that current flows through the microswitch 234 and conductor 302 to hold the relay 244 in its actuated condition.

The application of pressurized air to conduit 238 caused by actuation of. the valve solenoid 242 immediately causes the knife blade 60 to pivot in a clockwise direction as illustrated in FIG. 9 so that it rearmost edge engages the microswitch 234 and momentarily opens the microswitch. Opening of microswitch 234 breaks the circuit to the valve relay 242 and the valve returns to its initial position with line 238 being vented and line 236 receiving compressed air to return the knife blade 60 to the position illustrated in FIG. 9.

As the bag blank continues to move forwardly, its forward edge engages the switch actuator lever 253 of switch 252 to open the contacts of switch 252. No further change in the circuitry occurs until the forward edge of the bag engages the switch actuator 255 of switch 254 to close the contacts of switch 254. At this stage of the cycle, switches 250 and 254 are closed and switch 252 is open with all of the switch actuator arms riding on top of the bag.

The next step in the cycle of operation occurs when the trailing edge of the bag moves from beneath the lever 251 to cause the switch 250 to open. Continued movement of the bag causes the trailing edge of the bag to move from beneath the lever 253 to cause the switch 252 to close. Closure of the contacts of switch 252 immediately causes the flow of current from line L2 through conductor 305, the closed contacts of switch 254, line 307, the contacts of switch 252, line 306, the coil of relay 244, and line 300 to main power line L1.

Coil 242 is simultaneously actuated to actuate the valve 240, cylinder 232 and knife blade 60 to move through a cutting operation with the cutting operation being terminated by opening of the microswitch 234 in the manner previously discussed. It should be noted that opening of microswitch 234 deactivates the circuit to the valve solenoid 242 and the knife is consequently returned to its original position. It will be appreciated that the cycle of operation will continue with the knife blade being actuated as the switch actuator 253 drops over the trailing edge of each succeeding bag so that the knife will operate to sever the tape portion 58 along line 62 as illustrated in FIG. 8.

Should it be desired to go from a large bag size to a small bag size, it would be necessary to increase the speed of the chains 36 in order to maintain a desired close spacing between adjacent bags on the work conveyor belts 34. Otherwise, the adjacent bags would be separated a substantial distance with the connecting portion 58 between adjacent bags being overly long and resulting in overly long tags followed cutting of the tape along the cut line 62. Similarly, the speed of chains 36 would need to be adjusted to a lower speed when going from a small bag size to a larger bag size. All speed adjustments of chains 36 are effected by manual manipulation of knob 148 or knob 148 to position pointer 172 in alignment with the new bag size on dial 174.

Numerous modifications of the subject invention will undoubtedly occur to those skill in the art; for example, the invention is not limited to applications in which a tape is applied to the bag ends since it would be equally effective in operations in which the closure is effected solely by a sewing operation following by severing of the thread connecting the closed tube ends. Therefore, it should be understood that the spirit and scope of the invention is to be limited solely in light of the appended claims.

I claim:

1. Apparatus for feeding bag tubes to a sewing head for closing one end of the bag tubes by the sewing of a tape to the end being closed, said apparatus comprising frame means for supporting components of said apparatus, a sewing head mounted on the frame, a work conveyor adjacent said sewing head and having a work supporting run moving in an upstream direction to a downstream direction for feeding bag tubes consecutively to and through said sewing head at a constant speed with a given spaced interval between adjacent bags, an infeed conveyor for feeding bag tubes onto the upstream end of said work conveyor, selectively variable speed control drive means for driving said infeed conveyor and permitting adjustment of the relative speed of said infeed conveyor with respect to said work conveyor, tape feed means for feeding a closure tape to said sewing head to be sewn onto said bag ends whereby each bag leaving the sewing head is connected by a connecting portion of said tape to the next following bag, selectively operable tape cutter means for severing the connecting portion of said tape and stitching approximately medially between adjacent bags and tape cutter actuating means including bag sensing means for sensing bags on said work conveyor for actuating said cutter means to sever the tape between said bag members.

2. Apparatus for feeding bag tubes to a sewing head for closing one end of the bag tubes by a sewing operation on the end being closed, said apparatus comprising frame means for supporting components of said apparatus, a sewing head mounted on the frame, a work conveyor adjacent the sewing head and having a work supporting run moving in an upstream direction to a downstream direction for feeding bag tubes consecutively to and through said sewing head at a constant speed with a given spaced interval between adjacent bags, an infeed conveyor for feeding bag tubes on the upstream end of said work conveyor, selectively variable speed control drive means for driving said infeed conveyor and permitting adjustment of the relative speed of said infeed conveyor with respect to said work conveyor so that said sewing head sewingly closes said bag ends on said work conveyor and each bag leaving the sewing head is connected by a connecting portion of thread to the next following bag, selectively operable cutter means for severing the connecting portion of thread between adjacent bags and cutter actuating means including bag sensing means for sensing bags on said work conveyor for actuating said cutter means in response to the sensing of the bag members to sever the thread between said bag members downstream of the sewing head.

3. The invention of claim 2 wherein said infeed conveyor means comprises a plurality of driven chain members each having upwardly extending feed lugs.

4. The invention of claim 3 additionally including a conveyor power source for providing power for said work conveyor and said infeed conveyor, said variable speed control drive means comprising an infinitely variable speed transmission means connecting said conveyor power source to said infeed conveyor means and work conveyor power transmission means connecting said work conveyor to said conveyor power source.

5. The invention of claim 4 wherein said conveyor power source comprises the output of an infinitely variable speed primary transmission and additionally including a main drive motor drivingly connected to the input of said infinitely variable speed primary transmission.

6. The invention of claim 5 wherein said infeed conveyor includes continuously driven roller members extending between adjacent driven chain members and a side guide plate against which bag tubes positioned on said continuously driven rollers are positioned by the operation of said rollers for accurately positioning the ends of said bag tubes in alignment with said sewing head.

7. The invention of claim 6 wherein said tape cutter actuating means includes microswitch means positioned downstream of said sewing head successively engageable with bag members passing from said sewing head.

8. The invention of claim 7 wherein said work conveyor includes a plurality of parallel feed belts with said work supporting run comprising horizontal upper flights of said feed belts for supporting said bag tubes and additionally including hold-down means for holding down the end of said tubes moving through said sewing head.

9. The invention of claim 2 wherein the work supporting run of said work conveyor includes horizontal upper flights of a plurality of parallel feed belts and additionally including hold-down means for holding down the ends of said tubes moving through said sewing head.

10. The invention of claim 1 wherein said infeed conveyor means comprises a plurality of driven chain members each having upwardly extending feed lugs.

11. The invention of claim 10 additionally including a conveyor power source for providing power for said work conveyor and said infeed conveyor, said variable speed control drive means comprising an infinitely variable speed transmission means connecting said conveyor power source to said infeed conveyor means and work conveyor power transmission means connecting said work conveyor to said conveyor power source.

12. The invention of claim 11 wherein said conveyor power source comprises the output of an infinitely variable speed primary transmission and additionally including a main drive motor drivingly connected to the input of said infinitely variable speed primary transmission.

13. The invention of claim 12 wherein said infeed conveyor includes continuously driven roller members extending between adjacent driven chain members and a side guide plate against which bag tubes positioned on said continuously driven rollers are positioned by the operation of said rollers for accurately positioning the ends of said bag tubes in alignment with said sewing head.

14. The invention of claim 13 wherein said tape cutter actuating means includes microswitch means positioned downstream of said sewing head successively engageable with bag members passing from said sewing head.

15. The invention of claim 1 wherein said work conveyor includes a plurality of parallel feed belts with said work supporting run comprising horizontal upper flights of said feed belts for supporting said bag tubes and additionally including hold-down means for holding down the ends of said tubes moving through said 

1. Apparatus for feeding bag tubes to a sewing head for closing one end of the bag tubes by the sewing of a tape to the end being closed, said apparatus comprising frame means for supporting components of said apparatus, a sewing head mounted on the frame, a work conveyor adjacent said sewing head and having a work supporting run moving in an upstream directIon to a downstream direction for feeding bag tubes consecutively to and through said sewing head at a constant speed with a given spaced interval between adjacent bags, an infeed conveyor for feeding bag tubes onto the upstream end of said work conveyor, selectively variable speed control drive means for driving said infeed conveyor and permitting adjustment of the relative speed of said infeed conveyor with respect to said work conveyor, tape feed means for feeding a closure tape to said sewing head to be sewn onto said bag ends whereby each bag leaving the sewing head is connected by a connecting portion of said tape to the next following bag, selectively operable tape cutter means for severing the connecting portion of said tape and stitching approximately medially between adjacent bags and tape cutter actuating means including bag sensing means for sensing bags on said work conveyor for actuating said cutter means to sever the tape between said bag members.
 2. Apparatus for feeding bag tubes to a sewing head for closing one end of the bag tubes by a sewing operation on the end being closed, said apparatus comprising frame means for supporting components of said apparatus, a sewing head mounted on the frame, a work conveyor adjacent the sewing head and having a work supporting run moving in an upstream direction to a downstream direction for feeding bag tubes consecutively to and through said sewing head at a constant speed with a given spaced interval between adjacent bags, an infeed conveyor for feeding bag tubes onto the upstream end of said work conveyor, selectively variable speed control drive means for driving said infeed conveyor and permitting adjustment of the relative speed of said infeed conveyor with respect to said work conveyor so that said sewing head sewingly closes said bag ends on said work conveyor and each bag leaving the sewing head is connected by a connecting portion of thread to the next following bag, selectively operable cutter means for severing the connecting portion of thread between adjacent bags and cutter actuating means including bag sensing means for sensing bags on said work conveyor for actuating said cutter means in response to the sensing of the bag members to sever the thread between said bag members downstream of the sewing head.
 3. The invention of claim 2 wherein said infeed conveyor means comprises a plurality of driven chain members each having upwardly extending feed lugs.
 4. The invention of claim 3 additionally including a conveyor power source for providing power for said work conveyor and said infeed conveyor, said variable speed control drive means comprising an infinitely variable speed transmission means connecting said conveyor power source to said infeed conveyor means and work conveyor power transmission means connecting said work conveyor to said conveyor power source.
 5. The invention of claim 4 wherein said conveyor power source comprises the output of an infinitely variable speed primary transmission and additionally including a main drive motor drivingly connected to the input of said infinitely variable speed primary transmission.
 6. The invention of claim 5 wherein said infeed conveyor includes continuously driven roller members extending between adjacent driven chain members and a side guide plate against which bag tubes positioned on said continuously driven rollers are positioned by the operation of said rollers for accurately positioning the ends of said bag tubes in alignment with said sewing head.
 7. The invention of claim 6 wherein said tape cutter actuating means includes microswitch means positioned downstream of said sewing head successively engageable with bag members passing from said sewing head.
 8. The invention of claim 7 wherein said work conveyor includes a plurality of parallel feed belts with said work supporting run comprising horizontal upper flights of said feed belts for supporting said bag tubes and additionally including hold-down means for holding down the end of said tUbes moving through said sewing head.
 9. The invention of claim 2 wherein the work supporting run of said work conveyor includes horizontal upper flights of a plurality of parallel feed belts and additionally including hold-down means for holding down the ends of said tubes moving through said sewing head.
 10. The invention of claim 1 wherein said infeed conveyor means comprises a plurality of driven chain members each having upwardly extending feed lugs.
 11. The invention of claim 10 additionally including a conveyor power source for providing power for said work conveyor and said infeed conveyor, said variable speed control drive means comprising an infinitely variable speed transmission means connecting said conveyor power source to said infeed conveyor means and work conveyor power transmission means connecting said work conveyor to said conveyor power source.
 12. The invention of claim 11 wherein said conveyor power source comprises the output of an infinitely variable speed primary transmission and additionally including a main drive motor drivingly connected to the input of said infinitely variable speed primary transmission.
 13. The invention of claim 12 wherein said infeed conveyor includes continuously driven roller members extending between adjacent driven chain members and a side guide plate against which bag tubes positioned on said continuously driven rollers are positioned by the operation of said rollers for accurately positioning the ends of said bag tubes in alignment with said sewing head.
 14. The invention of claim 13 wherein said tape cutter actuating means includes microswitch means positioned downstream of said sewing head successively engageable with bag members passing from said sewing head.
 15. The invention of claim 1 wherein said work conveyor includes a plurality of parallel feed belts with said work supporting run comprising horizontal upper flights of said feed belts for supporting said bag tubes and additionally including hold-down means for holding down the ends of said tubes moving through said sewing head. 